Combined electric fuse and switch



Nov. 18, 1930. .1. R. TATE COMBINED ELECTRIC FUSE AND SWITCH Filed Augl5' 1928 INVENTUE.

Patented Nov. 18, 1930 UNITED @FFEQ 'T LMIEIS R. TA'IE, 0F TORONTO, ONTAR-O, CANADA, ASSEGNOR TO DOMTNION CUTO'UT COMPANY LELVIITED, F TGRGNTG, CANADA COMBINED ELECIB FUSE AND SWITCH Application led August 13, 1928. Serial No. 299,347.

This invention relates to heavyduty fused switches for outdoor and indoor use, which switches comprise a hollow body of insulating material having a contact adjacent each end thereof to which the lead wires are connected. A hollow plug member of insulating material is slidably litted in the body, which plug member is provided with spaced -contaets adapted to engage the contacts 1n the body and which are connected by a fusible element positioned within the plug. The

plug is provided with a head of insulating material which serves both as a handle for withdrawing the plug and as a-cap to cover the open end of the body and thus exclude dirt and moisture.

My object is to devise certain improvements in the details ot construction to overcome certain defects in the devices new on the market. One of these improvements is in the provision ot means for preventing the separation of the lcap from the plug while the latter is in position in the body.

Another improvement is in the method ot mounting the fusible element, and particularly the -method of ensuring good contact at the cap end ot the plug. Another improvement is in the construction of the contacts in the body.

I attain my object by means of the constructions hereinafter described and illustrated in the accompanying drawings in which Fig. 1 is a vertical section of the device;

Fig. 2 a cross section through the body on the line 2-2 in Fig. 1; and

Fig. 3 a cross section through the upper end of the plug.

In the drawings like numerals of reference indicate corresponding parts in the different figures.

1 is the hollow body of the device. which will usually be made of porcelain. TWithin the body a Jruse cartridge is adapted to slide so that it may be positioned to make or break the electric circuit in which the device is ineluded.

The body is counterbored at each end to receive metallic members 2 to each of which kare secured two opposed spring contacts 3.

Ypassage of conductors, the ends of which are secured in place by set screws 6.

The fuse cartridge is formed as a tube T of insulating material having at its upper end a contact 8 and at its lower end a contact 9. which are adapted to be engaged respectivelyI withv the upper and lower spring contacts A fusible element 10 inside the tube has itsV ends connected with the contact-s 8 and 9.

The lower contact 9 has a threaded eXtension 11 having a jam nut 12 thereon. On the outer end of the threaded extension is a shoulder 13 having a slot 14 formed therein. The end of the fusible element is passed through this slot 14 and bent around the extension 11, the nut 12 being turned down to hold the element against the shoulder 13. A coil spring 29 tends to prevent unscrewing of the nut.

The upper end oi the upper contact 8 has a recess 15 formed therein in which the upper end of the fusible element is bent. This recess is threaded to receive a plug 1G, the end of which is secured, by means of a lead seal, within a recess in the insulating cap 17.

This plug has a recess 18 therein in which is slidable a plunger 19. A. coil spring 2O is positioned in the recess below the plunger and tends to hold the latter in projected position. In the stein of the plunger is 'formed a notch 21 into which projects a shoulder 22 on the inside of the plug. This shoulder is preterably formed by driving a portion of the side of the plug inwardly by means ot a suitable punch. The plug will be formed of a metal suliciently soft to enable this to be done.

This plunger7 when the cap is in position on the end, the upper contact 8 resiliently holds the Jfusible element against the bottom of the recess 15.

As stated in the preamble of the specifica tion, it is desirable to prevent the removal of the cap from the fuse cartridge while the latter is in position in the body. l therefore mount on the upper contact 8 a thumb spring 23, which has connected therewith a locking member 2Lihaving a tongue 25 extending through a hole 26 in the side ofthe contact 8. The plugl has a ratchet notch or groove formed in its side into which the tongue 25 may project, one side of the groove forming a cam to move the tongue outwardly when the cap is being placed in position, the other side of the notch forming a shoulder 27 with which the tongue 25 engages to prevent the removal of the cap. After he fuse cartridge is withdrawn from the body, by pushing against the spring Q8 with the thumb, the

tongue may be withdrawn to allowl the cap to be removed.

In order to prevent moisture getting inside the body, an annular ring 28 of cork or other suitable material is secured within the cap to form a seal between the cap and body.

F rom the above description it will be seen that l have devised a construction which will satisfactorily attain the objects of my invention as set out in the preamble of this specilication.

`What l claim is:

l. n a combined fuse and switch,.thecom binatio-n of a fuse cartridgeV having spaced contact members thereon; a hollow body of Y insulating material in which the fuse cartridge is slidably received; spacedk contact 'members within said body adapted to be contacted by the contact members of the fuse cartridge, one of said body Contact members comprising'a metal member positioned within the bore of the body; and a. pair of opposed springs, each of said springs being of substantially elliptical form extending longitudinally ofthe body and secured to the metal member.

V2. In a combined fuse andV switch, the combination of a fuse cartridge having spaced contact members thereon; ahollow bony of insulating material in which the fuse cartridge is slidably received; spaced contact members within said body adapted to be contacted by the Contact members of the fuse cartridge, one of said body contact members comprising a metal member positioned withinthe bore of the body and a pair of opposed springs, each of said springs comprising a. strip of metal of substantially elliptical form, the opposite ends of said strip being secured to the metal member.

3. In a combined fuse and switch, the com bination of a fuse cartridge having spaced contact members thereon to whichthe fusible element is connected; a hollow body of insulating material in which the fuse cartridge is slidably received; spaced contact member-s y'within the body with which the contacts on the fuse cartridge are adapted to engage, one of the contact members on the fuse cartridge having a threaded tubular extension; an annular rib adjacent the outer end of said extension; and a jam nut threaded on said eX- tension adapted to hold the end of the fusible element against the rib.

4l. ln a combined fuse and switch, the combination of a fuse cartridge having spaced contact members thereon to which the fusible elementiis connected; a. hollow body of insulating material in which the fuse cartridge is slidably received; spaced contact members within the body with which the'contacts on the fuse cartridge are adapted to engage, one

of the contact members on the fuse cartridge within the body with which the contacts on"4 `the fuse cartridge are adapted to engage, one

ot the contact members on the fuse cartridge having a threaded tubular extension; an an nular shoulder on said extension; a am nut threaded on said extension adapted to hold the end of the fusible element against the shoulder; and a spring onsaid extension tending to hold the nut against the should r.V

6. ln a combined fuse and switch, the combination of a fuse cartridge having spaced contact members thereon to Vwhich a fusible element is connected; ahollow body ofinsulating material in which the fuse cartridge is slidably received; spaced contacts within the body with which the contacts on theV fuse cartridge are adapted to engage, one of the contacts' on the fuse cartridge having a threaded recess formed therein to receive the end of the fusible element; a cap of insulating material; a plug fitted in said cap and adapted to be threaded in said recess; and a resiliently pressed plunger carriedby the plug eX- tending into said recess to engage the fusible element.

7. ln a combined fuse and switch, the comfbination of a fuse cartridge having spaced contact members thereon to which a fusible element is connected; a hollow body of insulatingmaterial in which the fuse cartridge is slidably received; spaced contacts within the 'i material; a plug fitted in said cap and adapted to be threaded in said recess, said plug having a pocket formed therein; plunger slidable in said pocket; and a spring in said pocket tending to move the plunger into projected position.

8. In a combined fuse and switch, the coinbination of a fuse cartridge having spaced contact members thereon to which a fusible element is connected; a hollow body of insulating material in which the fuse cartridge is slidably received; spaced contacts within the body with which the contacts on the fuse cartridge are adapted to engage, one of the contacts on the fuse cartridge having a threaded recess formed therein to receive the end of the fusible element; a cap of insulating material; a. plug fitted in said cap and adapted to be threaded in said recess, said plug having a pocket formed therein; a plunger slidable in said pocket; and a spring in said pocket tending to move the plunger into projected position, said plunger having a slot formed in its side and the said plug having a shoulder on the wall of the pocket extending into said slot.

9. In a combined fuse and switch, the coinbination of a fuse cartridge having spaced contact members thereon to which a fusible element is connected; a hollow body of insulating material in which the fuse cartridge is slidably received; spaced contacts within the body with which the contacts on the fuse cartridge are adapted to engage; a cap of insu lating material detachably mounted on the upper contact member of the fuse cartridge; and means for locking said cap in position on the contact member inaccessible for release while the cartridge fuse is invposition in the body.

10. In a combined fuse and switch, the combination of a fuse cartridge having spaced cont-act members thereon to which a fusible element is connected; a hollow body of insulating material in which the fuse cartridge is slidably received; spaced contacts within the body with Which the contacts on the fuse cartridge are adapted to engage; a cap of insulating material threaded'on the upper contact member ofthe fuse cartridge; and means for preventing the disengagement of the cap from the contact member while the fuse cartridge is in the body.

11. In a combined fuse and switch, the combination of a fuse cartridge having spaced contact members thereon to which a fusible element is connected; a hollow body of insulating material in which the fuse cartridge is slidably received; spaced contacts within the body with which the contacts on the fuse cartridge are adapted to engage, the upper contact member on the fuse cartridge having a threaded recess formed thereon to receive the end of the fusible element; a cap of insulating material; a plug carried by the cap lof the plug and adapted to be screwed into said recess; a spring on said upper contact member, said upper contact member having a hole formed in its side; and a tongue on said spring extending through said hole, said plug having Y Alating material in which the fuse cartridge is slidably received; spaced contacts within the body with which the contacts on the fuse cartridge are adapted to engage, the upper contact member on the fuse cartridge having a threaded recess formed thereon to receive the end of the fusible element; a cap of insulating material; a plug carried by the cap and adapted to be screwed into said recess; a spring on said upper contactmember, said upper contact member having a. hole formed in its side; a tongue on said spring extending through said hole, said plug having a shoulder formed thereon with which said tongue is ai apted to engage to prevent the removal and a resiliently supported plunger carried by the plug extending into said recess.

13. In a combined fuse and switch, the combination of a fuse cartridge having spaced contact members thereon to which a fusible element is connected; a hollow body of insulating material in which the fuse cartridge is slidably received: spaced contacts within the body with which the contacts on the fuse cartridge are adapted to engage, the upper contact member on the fuse cartridge having a threaded recess formed thereon t0 receive the end of the fusible element; a cap of insulating material; a plug carried by the cap and adapted to be screwed into said recess; a spring on said upper contact member,

said upper contact member having a holek formed in its side; a tongue on said spring extending through said hole, said plug having a shoulder formed thereon with which said tongue is adapted to engage to prevent the removal of the plug, saidy plug having a' pocket formed therein; a plunger slidable in said pocket; and a spring in said pocket tending to move the plunger into projected position.

14. In a combined fuse and switch, the combination of a fuse cartridge having spaced contacts there-on to which a fusible element is` engaged; a hollow body of insulating material in which the fuse cartridge 1s slidably received; spaced contacts within the body.`

by the cap to retain the fusible element in en -v -gagement With'the contact on which said cap is mounted.

Y 15. In a combined fuse and switch, the combination of a fuse cartridge having spaced 5 contacts thereon towhich a fusible element is engaged; a hollow body of insulating material in which the fuse cartridge is slidably received; spaced contacts Within the body v with which the contacts on the fuse cartridge m are adapted to engage; a cap of insulating material mounted on one of the'contact members of the fuse cartridge, said last mentioned Contact member having a recess therein into. which the end of the fusible element extends; l

-15 and a projection carried by the cap adapted to extend into said recess to retain the fusible element in engagement With the bottom thereof. Y

' Vlo. In a combined fuse and switch, the com- 120 bination of a fuse cartridge havingspaced contacts thereon to which a fusible element is engaged; a hello-W body of insulating material in which the fuse cartridge is slida-bly received; spacedV contacts Within the bodj)7 Q5 with which the contacts on the fuse cartridge are adapted to engage; a cap of insulating material mounted on one of the contact members of the fuse cartridge, said last mentioned f Contact member having a recess therein into l y L'30 which the end of the fusible element extends;

and a resiliently pressed projection carried by the capA adapted to extend into said recess to retain the fusible element in engagement with the bottom thereof. Y

35 VSigned at Toronto', Canada, this 24th day of July 1928.

JAMES RICHARD TATE. 

